Strand-twisting mechanism



H. H. C. GRONDAHL.

STRAND TWISTING MECHANISM.

APPLICATION FILED JAN-18.19I9.

Patented Nov. 21, 1922..

Patented Nov. 21, 1922.

HANS HENRIK C. GRONDAHL, OF CHICAGO. ILLINOIS, 'ASSIGNOR TO WESTERN ELEC- TBIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

STRAND-TWISTING MECHANISM.

Application filed January 18, 1919. Serial No. 271,772.

T011]? whom if may concern:

Be it known that I. HANS HaNnIK C. GRoNnAnL, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Strand- Twisting Mechanism, of which the following is a full. clear, concise, and exact descript-ion.

This invention relates to strand twisting mechanism, and more particularly to a mechanism for twisting insulated switchboard conductors.

In certain forms of insulated conductors O in which the wires are insulated with compounds and fibrous material the compound forms a binder between the wire and braid which gives the conductor a certain stiffness, causing a complete twist given to it to spring back a certain amount when the conductor is left free.

It is the object of this invention to provide a. twisting mechanism which will eliminate this back twist from twisted conductors of this class thereby preventing this tendency to untwist which causes a collapse of the conductors in the coil in which they are formed after leaving the twisting machine.

In accordance with the general features of this invention mechanism is provided for applying to the twisted conductors a setting operation which will counteract this back twist tendency. One means for accomplishing this is by giving to the twisted conductors an additional twist in the same direction as the twist given to it by the twisting machine and then a twist in the opposite direction, which will counteract the first additional twist. the combined efi'ect of thesetwo twists being to overcome the spring tendency of the conductors to untwist.

In the drawings illustrating this invention Fig.1 is a view in side elevaion of a twisting machine with mechanism for performin this invention;

ig. 2 is a view in side elevation of a specific form of mechanism for removing the back twist from twisted conductors, and

Fig. 3 is a fragmentary detailed view on an enlarged scale of the driving mechanism for the back twist apparatus.

The invention is illustrated in connection with a. twisting machine such as shown in of turns, and to a suitable take-up Patent No. 1,263,405, issued April 23, 1918, 111 which wire supply reels 5 and 6 are mounted on a. stationary pedestal or support 7 around which revolves a tubular yoke 8. strands 10 and 11 drawn from the supply reels 5 and 6 are led downwardly through a guide opening 12 in the support 7 over a pulley 13, through one side of the tubular yoke 8, over a pulley 14, and over a capstan 15. A double twist is given to the strands 10 and 11, one as it leaves the guide 12 and passes over the pulley 13; a second as it leaves the pulley 14 and passes over the capstan 15.

The strand 16 thus twisted is passed a number of turns over the capstan 15, over an idler pulley 17, one turn over a back twist pulley 18, back over the capstan a number reel which is not shown. The back twist pulley 18 in addition to being rotated around its normal axis of rotation is also .rotated bodily at right angles to this axis of rotation.

This latter rotation is preferably accomplished through the agency of gears 20, 21, 22. and 23, the gear 2O being mounted upon one end of a spindle 24, on the other end of which is mounted a bevel pinion meshing with a bevel gear 26 upon the outer surface of the capstan 15. The gear 20 drives a second gear 21 mounted upon a spindle 27, upon which is also mounted a gear 22 meshing with the gear 23. The gear 23 is secured to a tubular frame 28 in which the back twist pulley 18 is rotatably mounted. The back twistv pulley 18 is so geared to the capstan 15 that it makes one complete revolution for each length of twist passing over it. That is, assuming that the capstan 15 is two feet in circumference and the length of twist is two inches, the back twist pulley 18 would make 12 revolutions for each revolution of the capstan 15.

The twisted strand from capstan 15 after passing over the idler pulley 17 is given an additional twist in the same direction as the twist given to it by the yoke 8. As it leaves the back twist pulley 18, however, another twist is put into it between this back twist pulley 18 and the capstan 15, but in the opposite direction to the twist put into it between the idler pulley 17 and the back twist pulley 18. The effect of this last twist is to counteract the'efiects of the twist put from any back twist or spring when taklen up onto the coiling reels.

The simplicity of the apparatus whereby it is readily adaptable to existing twisting machines and the beneficial resultswhich are obtained by its use in the handling of twisted conductors have proved the desirability and advantages of this invention.

What is claimed is:

1. In a strand twisting machine, a plurality of strands, a rotatable member for twisting the strands together, and means comprising a pulley rotatable about its axis in the direction of movement of the strand and bodily at right angles to its axis of rotation to divert the strands from their normal path and then back again to apply twists in opposite directions to the twisted strands for removing the back twists therefrom.

2. In a strand twisting machine, a plurality of strands, a rotating member for twisting the strands together, a capstan over which the twisted strands are drawn from the twisting member, a pulley over which the twisted strands are led back to the capstan, and means interposed between said pulley and capstan for givin said strands two twists in opposite directions as they pass between the pulley and the capstan.

3. In a strand twisting machine, a plurality of strands, a rotating member for twisting the strands together, a capstan over which the twisted strands are drawn from the twisting member, a pulley over which the twisted strands are led back to the capstan, and means interposed between the capstan and the pulley for giving the strands two twists in opposite directions, said means comprising a pulley rotatable about its axis in the dlrection of movement of the twisted strands and rotatable bodily at right angles to its direction of rotation around its axis.

4. In a strand twisting machine, a pliirality of strands, a rotating member for" 5. in a. strand twisting machine, a plurality of strands, a rotating member for twisting the strands together, a capstan over which the twisted strands are drawn from the twisting member, a pulley over which the strands are looped from the capstan, means comprising a pulley rotatable around its axis in the direction of movement of the strands and rotatable bodily at right angles to its axis for giving the strands two twists in opposite directions, and gears interposed between said means and the capstan for driving said means.

In witness whereof, I hereunto subscribe my name this 7th day of January A. D.,

HANS HENRIK O. GRONDAHL. 

